Evaluating Wind Erosion Problems With WEPS

Haakon County, South Dakota

Following are some example problems that we will use to evaluate some wind erosion problems in Haakon County, South Dakota.

Situation 1: A two year rotation

The scenario for the problem is:

. The farm is located in Haakon County, SD
. The Cligen station is Milesville and the Windgen station is Pierre Municipal
. The Soil Map Unit used in the evaluation is: Craft Cv 85 VFSL
. The original 2 year cropping system is Winter Wheat-Fallow
. The field size is: x axis - 2600 ft.; y axis - 2600 ft.
. Orientation of field operations and rows is - North (0 or 360 degrees)
. Operations are performed parallel to x axis
. The early WEPS evaluations will be run for 5 rotation cycles
. Barriers - None

Below is the 2 year rotation of Winter Wheat and Fallow, including the dates and field operations (Fig. 1).

*Winter Wheat (32 bu. yield) - Fallow (Conventional)

Figure 1. A 2 year rotation of Winter Wheat and Fallow.

When we expand the 2 year rotation to include Forage Sorghum/Sudan Grass Cross (Kane) (Fig. 2), we can add the operations, dates of operation, and the Kane crop directly to the 2 year rotation or we can build a separate template for Kane. The new template can then be inserted into the rotation. We recommend the option of building the separate template for Kane and the template will then be available the next time you are building a rotation that includes that crop.

Figure 2. A one year rotation of Forage Sorghum/Sudan Grass Cross(Kane).

Below is the 3 year rotation of Winter Wheat; Fallow; and Kane, including the field operations and the dates they were performed (Fig. 3).

*Winter Wheat (32 bu. yield) - Fallow (Conventional) and Kane (~ 6000 lbs.)

Figure 3. A 3 year rotation of Winter Wheat; Fallow; and Kane.